Jakub Kicinski [off-list ref]

Sent: Saturday, April 17, 2021 5:50 AM

quoted

+	switch (tp->version) {
+	case RTL_VER_10:
+		data = ocp_reg_read(tp, 0xad40);
+		data &= ~0x3ff;
+		data |= BIT(7) | BIT(2);
+		ocp_reg_write(tp, 0xad40, data);
+
+		data = ocp_reg_read(tp, 0xad4e);
+		data |= BIT(4);
+		ocp_reg_write(tp, 0xad4e, data);
+		data = ocp_reg_read(tp, 0xad16);
+		data &= ~0x3ff;
+		data |= 0x6;
+		ocp_reg_write(tp, 0xad16, data);
+		data = ocp_reg_read(tp, 0xad32);
+		data &= ~0x3f;
+		data |= 6;
+		ocp_reg_write(tp, 0xad32, data);
+		data = ocp_reg_read(tp, 0xac08);
+		data &= ~(BIT(12) | BIT(8));
+		ocp_reg_write(tp, 0xac08, data);
+		data = ocp_reg_read(tp, 0xac8a);
+		data |= BIT(12) | BIT(13) | BIT(14);
+		data &= ~BIT(15);
+		ocp_reg_write(tp, 0xac8a, data);
+		data = ocp_reg_read(tp, 0xad18);
+		data |= BIT(10);
+		ocp_reg_write(tp, 0xad18, data);
+		data = ocp_reg_read(tp, 0xad1a);
+		data |= 0x3ff;
+		ocp_reg_write(tp, 0xad1a, data);
+		data = ocp_reg_read(tp, 0xad1c);
+		data |= 0x3ff;
+		ocp_reg_write(tp, 0xad1c, data);
+
+		data = sram_read(tp, 0x80ea);
+		data &= ~0xff00;
+		data |= 0xc400;
+		sram_write(tp, 0x80ea, data);
+		data = sram_read(tp, 0x80eb);
+		data &= ~0x0700;
+		data |= 0x0300;
+		sram_write(tp, 0x80eb, data);
+		data = sram_read(tp, 0x80f8);
+		data &= ~0xff00;
+		data |= 0x1c00;
+		sram_write(tp, 0x80f8, data);
+		data = sram_read(tp, 0x80f1);
+		data &= ~0xff00;
+		data |= 0x3000;
+		sram_write(tp, 0x80f1, data);

These are the parameters of PHY.
Some are used for speed down about power saving.
And some are used for performance.

quoted

+	switch (tp->version) {
+	case RTL_VER_12:
+		ocp_reg_write(tp, 0xbf86, 0x9000);
+		data = ocp_reg_read(tp, 0xc402);
+		data |= BIT(10);
+		ocp_reg_write(tp, 0xc402, data);
+		data &= ~BIT(10);
+		ocp_reg_write(tp, 0xc402, data);
+		ocp_reg_write(tp, 0xbd86, 0x1010);
+		ocp_reg_write(tp, 0xbd88, 0x1010);
+		data = ocp_reg_read(tp, 0xbd4e);
+		data &= ~(BIT(10) | BIT(11));
+		data |= BIT(11);
+		ocp_reg_write(tp, 0xbd4e, data);
+		data = ocp_reg_read(tp, 0xbf46);
+		data &= ~0xf00;
+		data |= 0x700;
+		ocp_reg_write(tp, 0xbf46, data);

These are used to adjust the clock of GPHY.
It influences the linking.

quoted

+	data = r8153_phy_status(tp, 0);
+	switch (data) {
+	case PHY_STAT_EXT_INIT:
+		rtl8152_apply_firmware(tp, true);
+
+		data = ocp_reg_read(tp, 0xa466);
+		data &= ~BIT(0);
+		ocp_reg_write(tp, 0xa466, data);

These let the PHY exit PHY_STAT_EXT_INIT state.

What are all these magic constants? :(

I think it is difficult for me to make all magic values meaningful.
The PHY setting is very complex. Only PHY engineers know
what are the settings mean.

quoted

@@ -6878,7 +8942,11 @@ static int rtl8152_probe(struct usb_interface

*intf,

quoted

 	set_ethernet_addr(tp);

 	usb_set_intfdata(intf, tp);
-	netif_napi_add(netdev, &tp->napi, r8152_poll, RTL8152_NAPI_WEIGHT);
+
+	if (tp->support_2500full)
+		netif_napi_add(netdev, &tp->napi, r8152_poll, 256);

why 256? We have 100G+ drivers all using 64 what's special here?

quoted

+	else
+		netif_napi_add(netdev, &tp->napi, r8152_poll, 64);

We test 2.5G Ethernet on some embedded platform.
And we find 64 is not large enough, and the performance
couldn't reach 2.5 G bits/s.

Best Regards,
Hayes